| 摘要 |
PURPOSE:To obtain shield against alpha-ray, preferable heat resistance and etching workability by coating an active region on a semiconductor element with a polyimide protective film having much smaller thermal expansion coefficient as compared with general polymer. CONSTITUTION:After a semiconductor element 2 is mounted on a ceramic package 3 and wire bonded, an alpha-ray shielding film 1 is coated on the surface of the element 2, and sealed with a metal plate 5. Polyimide having linear thermal expansion coefficient of 3.0X10<-5>K<-1> or less is used for the film 1. Thus, a shield can be formed against alpha-ray. Since the used polyimide has excellent heat resistance and moisture resistance with low thermal expansion coefficient, a semiconductor device coated protectively by the resin material has excellent heat shock resistance, less damage and high reliability. |
